The Experts below are selected from a list of 30 Experts worldwide ranked by ideXlab platform
David Highton - One of the best experts on this subject based on the ideXlab platform.
-
determination of the blockage effect on a thermal Anemometer using a small open jet wind tunnel
17th International Congress of Metrology, 2015Co-Authors: Stephen R Rickaby, David HightonAbstract:When an object, specifically an Anemometer, is presented before a wind tunnel the flow field will be altered deflecting the flow around the Anemometer creating what is commonly known as the Blockage Effect. Directly comparing a thermal Anemometer with a Vane Anemometer in the same flow field, the velocity measured by the thermal Anemometer may be significantly different to that measured by the Vane Anemometer as a result of blockage. In this paper we consider the blockage created by a thermal Anemometer. A simple mathematical model is derived to directly compare the thermal Anemometer with a primary standard Vane Anemometer. The calibration results obtained are compared with those obtained by the manufacturer and an ISO/IEC 17025 accredited laboratory chosen as the Reference Laboratory for the purposes of the paper. We conclude with an analysis of the results, discussing the differences in the measured output and postulating how these results may be unified.
-
erratum to determination of the blockage effect on a thermal Anemometer using a small open jet wind tunnel
17th International Congress of Metrology, 2015Co-Authors: Stephen R Rickaby, David HightonAbstract:Due to problems that have occurred during the conversion of the article into PDF format, and the resulting loss of many special characters, a new correct version of the article is published below. When an object, specifically an Anemometer, is presented before a wind tunnel the flow field will be altered deflecting the flow around the Anemometer creating what is commonly known as the Blockage Effect. Directly comparing a thermal Anemometer with a Vane Anemometer in the same flow field, the velocity measured by the thermal Anemometer may be significantly different to that measured by the Vane Anemometer as a result of blockage. In this paper we consider the blockage created by a thermal Anemometer. A simple mathematical model is derived to directly compare the thermal Anemometer with a primary standard Vane Anemometer. The calibration results obtained are compared with those obtained by the manufacturer and an ISO/IEC 17025 accredited laboratory chosen as the Reference Laboratory for the purposes of the paper. We conclude with an analysis of the results, discussing the differences in the measured output and postulating how these results may be unified.
Stephen R Rickaby - One of the best experts on this subject based on the ideXlab platform.
-
determination of the blockage effect on a thermal Anemometer using a small open jet wind tunnel
17th International Congress of Metrology, 2015Co-Authors: Stephen R Rickaby, David HightonAbstract:When an object, specifically an Anemometer, is presented before a wind tunnel the flow field will be altered deflecting the flow around the Anemometer creating what is commonly known as the Blockage Effect. Directly comparing a thermal Anemometer with a Vane Anemometer in the same flow field, the velocity measured by the thermal Anemometer may be significantly different to that measured by the Vane Anemometer as a result of blockage. In this paper we consider the blockage created by a thermal Anemometer. A simple mathematical model is derived to directly compare the thermal Anemometer with a primary standard Vane Anemometer. The calibration results obtained are compared with those obtained by the manufacturer and an ISO/IEC 17025 accredited laboratory chosen as the Reference Laboratory for the purposes of the paper. We conclude with an analysis of the results, discussing the differences in the measured output and postulating how these results may be unified.
-
erratum to determination of the blockage effect on a thermal Anemometer using a small open jet wind tunnel
17th International Congress of Metrology, 2015Co-Authors: Stephen R Rickaby, David HightonAbstract:Due to problems that have occurred during the conversion of the article into PDF format, and the resulting loss of many special characters, a new correct version of the article is published below. When an object, specifically an Anemometer, is presented before a wind tunnel the flow field will be altered deflecting the flow around the Anemometer creating what is commonly known as the Blockage Effect. Directly comparing a thermal Anemometer with a Vane Anemometer in the same flow field, the velocity measured by the thermal Anemometer may be significantly different to that measured by the Vane Anemometer as a result of blockage. In this paper we consider the blockage created by a thermal Anemometer. A simple mathematical model is derived to directly compare the thermal Anemometer with a primary standard Vane Anemometer. The calibration results obtained are compared with those obtained by the manufacturer and an ISO/IEC 17025 accredited laboratory chosen as the Reference Laboratory for the purposes of the paper. We conclude with an analysis of the results, discussing the differences in the measured output and postulating how these results may be unified.
Sluse Jan - One of the best experts on this subject based on the ideXlab platform.
-
Influence of blockage effect on measurement by Vane Anemometers
EDP Sciences, 2017Co-Authors: Sluse JanAbstract:The article deals with influence of blockage effect caused by Vane Anemometer in the wind tunnel by measurement via this Anemometer. The influences will be represented by correction coefficient. The first part of this article is focused on the design of the impeller of Vane Anemometers. The impellers are printed on 3D printer with variable parameters. The Anemometer is fixed in an open section of the wind tunnel with closed loop and the velocity profile is measured by Laser Doppler velocimetry (LDV) in front and behind it for all impellers. The experimental data are compared with the numerical simulation in OpenFOAM. The results are correction coefficients
Pawel Ligeza - One of the best experts on this subject based on the ideXlab platform.
-
an alternative mathematical model of Vane Anemometers based on the balance of power
Flow Measurement and Instrumentation, 2017Co-Authors: Pawel LigezaAbstract:Abstract Anemometers based on the exchange of momentum between the flow and rotating measuring element comprise an important class of instruments used in flow metrology, especially in meteorological and ventilation measurements. In these instruments, overvaluation of the measured average velocity, caused by the inertia of their rotors, takes place. To analyse this phenomenon and the dynamics of the measurement process, as well as to estimate and minimize the measurement uncertainty, it is required to be acquainted with the mathematical model of the Anemometer. In this study, the model of the Vane Anemometer based on the equation of motion of its rotor available in the literature is analysed, and a new model based on the power balance is proposed. Model testing and a comparison of both models has also been performed.
Pawel Jamroz - One of the best experts on this subject based on the ideXlab platform.
-
effect of the continuous traverse trajectory and dynamic error of the Vane Anemometer on the accuracy of average velocity measurements at the cross section of the mine heading model based testing
Archives of Mining Sciences, 2014Co-Authors: Pawel JamrozAbstract:This paper discusses the problem of measuring the average velocity at the cross-section of mine heading with the use of the continuous traverse method. Based on model testing, it has been shown that measurement signals, obtained along the traversing trajectory, belong to the group of non-stationary signals. The methodology of the traversing method measurements, with the aspect of capabilities of measuring instruments used for that purpose, has been analysed. Results of simulation tests concerning the dynamic response of a Vane Anemometer to the measurement signal for selected trajectories of the continuous traverse have been presented. For this purpose, a velocity profile presenting an expanded stream of undisturbed air flow in the excavation has been used. Attention has been paid to the problem of selecting an adequate trajectory of Anemometer movement, as the value of the velocity measured at the cross-section depends on the trajectory.
